In automation technology, data transmission often occurs via electrical current circuits, which are galvanically isolated from one another, respectively galvanically decoupled. Since, in the case of galvanically isolated connections, electrical potentials are isolated from one another, one speaks also of potential-free connections. Important is the application of galvanically isolated, electrical current circuits especially in field devices, such as sensors, actuators, valves, etc., in explosion endangered areas.
A known method for data transmission involves the so-called print transformer. In the case of print, or also spiral or planar, transformers, used as transformer are two spiral shaped, conductive traces arranged lying opposite one another in or on a circuit board. Transmission of the data occurs via inductive coupling, whereby galvanic isolation is assured. A corresponding solution is disclosed, for example, in U.S. Pat. No. 7,852,186 B2.
Print transformers are often also applied in integrated circuits. They can be integrated relatively simply into the metal plies.